modified:   flocker/node/_config.py
	modified:   flocker/node/_model.py
	modified:   flocker/node/test/test_config.py
	modified:   flocker/node/test/test_model.py
	modified:   flocker/node/gear.py
	modified:   flocker/node/gear.py
	modified:   flocker/node/gear.py
	modified:   flocker/node/test/test_gear.py
	modified:   flocker/node/_config.py
	modified:   flocker/node/_model.py
	modified:   flocker/node/test/test_config.py
	modified:   flocker/node/test/test_model.py
added test for fix to `frozenset` \s of `Application` instances
lint fixes
	modified:   flocker/node/functional/test_gear.py
    use frozenset for environment variables
	modified:   flocker/node/functional/test_gear.py
lint fix
comment updated; env vars are returned as frozenset now, not dict
addresses review comments
Merge pull request #596 from ClusterHQ/erroneous-wrong-arguments-595

Erroneous wrong arguments 595